FDA Removes Clinical Hold on Phase I/II Study of Angelman Syndrome Treatment

GeneTx Biotherapeutics and Ultragenyx Pharmaceutical announced that FDA has removed the clinical hold on GTX-102 (antisense oligonucleotide), an investigational treatment for Angelman syndrome that the companies have partnered to develop. FDA also gave the go-ahead for GeneTx to begin dosing naïve pediatric patients with Angelman syndrome in the Phase I/II study of GTX-102. Under a separate agreement, GeneTx previously received clearance to begin the Phase I/II study in the UK and Canada.

“The dosing protocol across the three regions is designed to provide a broad picture on dose response to inform loading and maintenance regimens as we move to the next phase of development,” said Scott Stromatt, MD, CMO of GeneTx. “We are working with urgency to begin treating study participants in all three regions over the next several months recognizing that there is no approved therapy available for the Angelman community.”

Eight patients (4 to 8 years of age) who were not previously treated with GTX-102 will be enrolled into two groups under the amended US protocol. These groups include an active group (that will receive four monthly 2-mg doses of GTX-102) and an age-matched comparator group (which will have limited assessments). Patients in the comparator group will then be eligible to receive GTX-102 under the same dosing strategy as the active group.

The safety, tolerability, and plasma and cerebrospinal fluid concentrations of GTX-102 in pediatric patients with Angelman syndrome with a genetically confirmed diagnosis of full maternal UBE3A gene deletion are evaluated in the Phase I/II study.

Source: Ultragenyx